Most of the components of power system generation, transmission or distribution facilities, such as transmission lines, step-up and step-down transformers, power breakers and generators are monitored and controlled. The control and monitoring is usually performed by electromechanical or electronic equipment that are able to measure electrical quantities, perform calculations based on pre-defined algorithms and thresholds and actuate the system when necessary. Due to the high voltage, current and power flowing through the high-power components, current transformers, potential transformers and breakers are employed as an interface between the high-power components and the low-power control and monitoring devices such as a medium to high voltage monitoring circuit. This medium to high voltage monitoring circuit and its associated circuitry are tested by technicians. For example, a technician might test the operation of a medium to high voltage monitoring circuit or its associated circuitry by inserting a test plug into an interface test device and performing various tests. Unfortunately, it is inevitable that mistakes happen during such testing which results in damage to the equipment or harm to the technician. During such testing, the technician might also adjust the medium to high voltage monitoring circuit by changing the parameters of the medium to high voltage monitoring circuit based upon the testing or based upon other factors. Unfortunately, such testing and adjustments take substantial amounts of the technician's time which is expensive. Furthermore, it is typical to perform period maintenance on the circuitry of the medium to high voltage monitoring circuits. In order to perform maintenance on medium to high voltage monitoring circuits, the associated power circuits must be powered down to allow the technician to perform the maintenance since the interface or other components in the medium to high voltage monitoring circuit might otherwise be damaged. These interruptions in operation of the medium to high voltage monitoring circuit and in the power circuit increase the cost of operation. For example, there are costs associated with switching to another power circuit and there are costs associated with the lost usage of the equipment powered by the power circuit. Accordingly, there is a strong need in the art to improve medium to high voltage monitoring circuits and their associated circuitries to reduce or eliminate the aforementioned drawbacks.